Brett Eldredge has shared a new song that he wrote for his big brother, Brice, in honor of his wedding day. The country singer took to Instagram to share footage of himself performing the sweet song during his brother's wedding reception.

"I woke up very emotional in the middle of the night a few months ago with the realization that my big brother was about to get married and that we were no longer kids anymore," he wrote in the caption. "I had been putting off writing my best man speech until it came to me at 3am and I wrote the whole thing in bed that night."

He continues, "My brother is a great man and is my first call when life comes at me sideways. He and his incredibly smart and beautiful wife Lori are gonna have an awesome life together and I couldn’t be more happy for them...so here’s my best man speech, i didn’t write it for an album or any project, I wrote it for my brother, and though it’s almost impossible to sing through the tears, hopefully you will at least hear my heart for my brother, my best friend...here's my "Best Man Speech."

The video shared show Eldredge on a small stage at the reception singing the heartfelt words from the bottom of his heart while strumming his guitar. "So when you start a family of your own / Hope your kids run wild like we did back at home / Barefoot in the grass / Never thinking we would grow up fast / And then we did," he sings in the chorus.

In addition to the video, Eldredge also shared a photo from the wedding day of him standing next to his brother on a beach. See the post below to hear the "Best Man Speech" and make sure you have a box of kleenex nearby.